1. Field of the Invention
The present invention is generally directed to the field of semiconductor processing, and, more particularly, to a method of forming a trench isolation on semiconductor devices.
2. Description of the Related Art
In modern semiconductor fabrication, many thousands of integrated circuits are formed above the surface of a semiconducting substrate. In order that these various circuits properly operate, they must be electrically isolated from one another. Isolations are regions formed on an integrated circuit device to electrically isolate the various components and/or circuits of an integrated circuit device. One type of isolation commonly employed in the manufacture of integrated circuit devices is a trench isolation.
Typically, after such trench isolations are formed, the top surface of the isolation is subjected to one or more chemical mechanical polishing operations during the course of manufacturing the integrated circuit device. Additionally, such trench isolations, when comprised of a dielectric material, such as TEOS, have been subject to excessive dishing. Moreover, during subsequent processing of the semiconductor device, the height of such an isolation may be further reduced by the various cleanings of the semiconductor device to remove, for example, regions of native oxide that may have formed. This excessive dishing and reduction in the overall height of the isolation can cause many problems in the ultimate finished integrated circuit device. For example, if dishing becomes excessive, or if the isolation becomes too short, then there is a danger of exposure or insufficient coverage of the junction between the surface of the silicon substrate and the edge of the trench formed in the substrate. Such inadequate, or incomplete, insulation of that region may cause many problems. For example, various conductors are run across these isolations to electrically connect various integrated circuit devices. If there is insufficient insulation between these current conductors and the substrate, then current leakage may occur into the substrate.
The present invention is directed to a semiconductor device that minimizes or reduces some or all of the aforementioned problems and a method of making same.